WASHINGTON — Slovenia signed the Artemis Accords outlining best practices for sustainable space exploration April 19, the third European country to do so in five days.

Matevž Frangež, state secretary of the ministry of the economy, tourism and sport in the Slovenian government, signed the Accords in a ceremony in Ljubljana, Slovenia. It took place as part of the broader U.S. – Slovenia Strategic Dialogue held there that day.

“Slovenia joins the principles, values and rules on the peaceful use of space as a common good of humanity,” Frangež said in a statement.

The Artemis Accords, unveiled in 2020, describe practices that signatory nations should follow in space exploration, building upon the Outer Space Treaty of 1967 and related international agreements. They include provisions on transparency and interoperability as well as preservation of space heritage, utilization of space resources and deconfliction of space activities.

Slovenia is the 39th nation to sign the accords. The country, a member of the European Union, has been an associate member of the European Space Agency since 2016. In November 2023, the Slovenian government formally petitioned to become a full member of ESA, having adopted a national space strategy that was the final formal milestone before seeking full membership. The ESA Council is expected to decide on Slovenia’s membership later this year.

“It opens up opportunities for Slovenia to accelerate the development of our space sector,” Frangež said when Slovenia submitted its request for full ESA membership during a European Space Summit in Seville, Spain. “This is not only an opportunity to strengthen space research but also to develop breakthrough innovations that can revitalize the Slovenian economy.”

Through the Artemis Accords, Slovenia is seeking greater cooperation with the United States in space as well. “We recognize Slovenia as a rising leader in space,” said Jamie Harpootlian, the U.S. ambassador to Slovenia, in a statement about the Artemis Accords signing. “We look forward to taking our collaborations with Slovenia on science, technology and innovation to new frontiers.”

Slovenia is the third European country to sign the accords in less than a week. Switzerland signed the Artemis Accords in a ceremony at NASA Headquarters April 15. A day later, Sweden signed the accords at an event in Stockholm. Three other countries have also signed the accords so far this year: Belgium, Greece and Uruguay.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...